Pyramidal cells steer interneuron fate to shape cortical circuits

A Nature study shows pyramidal neuron subtypes actively sculpt cortical interneuron diversity by promoting their survival and terminal differentiation; in Fezf2 mutants lacking L5b pyramidal neurons, SST interneurons alter programmed cell death and PVALB interneurons switch subtype identity, via activity-independent PN–interneuron signaling and multiple molecular pathways, with a bioinformatic screen identifying candidate ligands and adhesion molecules.